There is a conventional cutting insert in which cutting edges are formed with nicks. For example, the cutting insert in Patent Document 1 is for rotary cutting, and this cutting insert is provided, in a side surface thereof, with a plurality of grooves (hereinafter referred to as “nicks”) so as to separate a major cutting edge thereof into portions. Since such nicks separate the major cutting edge into portions, chips which are to be discharged via cutting by the major cutting edge can be made smaller, whereby cutting resistance during cutting can be reduced.